JP5929809B2 - Firmware update method and firmware program - Google Patents

Description

  The present invention relates to a firmware update method and a firmware program having an update function.

  The operations executed by the image forming apparatus such as a printer are controlled by a control program (hereinafter referred to as firmware) incorporated in the apparatus in advance. The firmware can reproduce the setting contents set individually such as the print setting, for example, by reading the parameters stored in the memory.

  In the case of updating such firmware, the parameter arrangement information before and after the firmware update is different, so the parameter before and after the firmware update must be reset. There is known a method of writing on (Random Access Memory) and rearranging the written parameters in accordance with the arrangement information after the firmware update.

  For example, in Patent Document 1, parameters stored in a memory in a binary format are converted into a text format and written out, so that parameters can be read more easily than reading in a binary format, which is appropriately read depending on firmware specifications. A firmware update method that can be taken over has been proposed.

JP 2009-254513 A

  However, in the prior art, there is a case where encrypted information including a control code, for example, confidential information such as a password, cannot be correctly restored to the original binary data by converting the binary format parameter to the text format. There was a problem.

In order to solve the above-mentioned problem, a firmware update method according to the present invention is a method for updating firmware for operating a device with reference to a parameter setting value stored in a first nonvolatile memory, A firmware update step for updating, a parameter definition read step before update for reading, from the second nonvolatile memory, parameter definition information including the parameter identifier and arrangement information of the firmware before update after updating the firmware , A pre-update memory image creation step for creating a memory image in the same format as the parameter setting value stored in the first nonvolatile memory before the firmware update, and reading the parameter setting value before the firmware update from the memory image Parameter identifier and A pre-update parameter setting value holding step that is linked and held in the memory, and a parameter setting value that rearranges the parameter setting value before firmware update held in the memory according to the parameter arrangement information after firmware update in the memory image A rearrangement step, a first nonvolatile memory writing step for copying the memory image in which the parameter setting values are rearranged to the first nonvolatile memory, and the firmware parameter definition information after the firmware update. And a second nonvolatile memory writing step for writing the data on the second nonvolatile memory.

A firmware program according to the present invention is a firmware program for updating firmware for operating a device with reference to parameter setting values stored in a first nonvolatile memory, the firmware update program for updating the firmware, After updating the firmware , the parameter definition read program before update that reads parameter definition information including the parameter identifier and arrangement information of the firmware before update from the second nonvolatile memory, and the firmware before updating the firmware on the memory A pre-update memory image creation program for creating a memory image of the same format as the parameter setting values stored in the first nonvolatile memory; and a parameter reading value for reading the parameter setting values before the firmware update from the memory image A parameter setting value holding program before update to be held in the memory in association with a different child, and a parameter for rearranging the parameter setting value before firmware update held in the memory according to the parameter arrangement information after firmware update to the memory image A setting value rearrangement program, a first nonvolatile memory writing program for copying the memory image in which parameter setting values are rearranged to the first nonvolatile memory, and the firmware parameters after the firmware update And a second nonvolatile memory writing program for writing definition information on the second nonvolatile memory.

A firmware program according to the present invention is a firmware program for updating firmware for operating a device with reference to parameter setting values stored in a first nonvolatile memory, the firmware update program for updating the firmware, Before update of the firmware, the parameter definition read program before update for reading parameter definition information including the parameter identifier and arrangement information of the firmware before update from the second nonvolatile memory, and the firmware before updating the firmware on the memory A pre-update memory image creation program for creating a memory image of the same format as the parameter setting value stored in the first nonvolatile memory; and reading the parameter setting value before firmware update from the memory image; A parameter setting value holding program before update stored in the memory in association with a child, and a parameter setting for rearranging the parameter setting value before firmware update held in the memory according to the parameter arrangement information after firmware update in the memory image A value relocation program, a first non-volatile memory writing program for copying the memory image in which parameter setting values are relocated to the first non-volatile memory, and the firmware parameter definition after the firmware update And a second nonvolatile memory writing program for writing information onto the second nonvolatile memory.
It is said.

  According to the present invention, it is possible to update the firmware before update in the binary format based on the parameter specification, and it is possible to handle the encrypted data that cannot be handled in the text format. And a firmware program can be provided.

2 is a functional block diagram illustrating a functional configuration of the image forming apparatus. FIG. It is the schematic explaining the parameter specification before firmware update. It is the schematic of the virtual EEPROM by which the setting parameter of EEPROM before firmware update was copied to RAM. It is the schematic of the virtual EEPROM initialized by the parameter specification after firmware update. It is the schematic of the virtual EEPROM which rewritten the virtual EEPROM to the setting parameter before firmware update. It is a figure explaining the creation and update method of virtual EEPROM. It is a figure explaining the state temporarily saved in RAM, in order to initialize virtual EEPROM with the parameter specification after firmware update. It is the schematic explaining the parameter specification after firmware update. It is a flowchart explaining the process for reflecting the setting parameter before firmware update in the setting parameter for operating the firmware after update. It is the schematic explaining the parameter specification before firmware update. It is the schematic explaining the parameter specification after firmware update. It is a flowchart explaining the process for reflecting the setting parameter before firmware update in the setting parameter for operating the firmware after update.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, this invention is not limited to the following description, In the range which does not deviate from the summary of this invention, it can change suitably.

[First Embodiment]
In the description of the first embodiment, an image forming apparatus to which the firmware program according to the present invention is applied will be described as an example, and the firmware update method will be described.

  FIG. 1 is a functional block diagram illustrating the functional configuration of the image forming apparatus 100. The image forming apparatus 100 includes a CPU (Central Processing Unit) 101, a receiving unit 102, an image processing unit 103, a printing unit 104, and an EEPROM (Electrically Erasable Programmable Read-Only Memory) 105 as a first nonvolatile memory. A RAM 107 as a memory, a Flash A 109, a Flash B 112 as a second non-volatile memory, a medium paper feeding unit 115, and a power supply unit 116, and an image based on the data received via the receiving unit 102. It is an apparatus capable of printing on a medium such as paper.

  The CPU 101 is connected to the receiving unit 102, the image processing unit 103, the printing unit 104, the EEPROM 105, the RAM 107, the Flash A 109, the Flash B 112, the medium feeding unit 115, and the power supply unit 116 via the system bus 114, and the image forming apparatus 100 overall control.

  The receiving unit 102 is a data receiving unit that receives data transmitted from, for example, an external communication device (not shown) connected via a USB (universal serial bus) or a network, or a PC (Personal Computer).

  The image processing unit 103 is a print data generation unit that converts the data received via the reception unit 102 or the data accumulated in the image forming apparatus 100 into print data that can be printed by the printing unit 104 and is generated.

  The printing unit 104 is an output unit that includes an electrophotographic print engine, for example, and prints the print data generated by the image processing unit 103 on paper as a medium for output.

  The EEPROM 105 is a non-volatile memory that can be rewritten a plurality of times by an electrical signal, and retains information even when power supply to the image forming apparatus 100 is stopped. The EEPROM 105 holds a setting parameter 106 that defines operation settings of the image forming apparatus 100.

  A RAM 107 is a volatile memory, and temporarily stores data received via the receiving unit 102 and print data generated by the image processing unit 103. Further, the RAM 107 holds a virtual EEPROM 108 that is parameter data in the same format as the setting parameter 106 for rearranging the setting parameter 106 in the EEPROM 105 based on a parameter specification after firmware update described later.

  The flash A 109 is a non-volatile memory that can be rewritten a plurality of times by an electric signal, and retains information even when power supply to the image forming apparatus 100 is stopped. The flash A 109 holds firmware 110 that controls the operation of the image forming apparatus 100. The firmware 110 is a program for controlling the operation of the image forming apparatus 100, and has a parameter specification 111 after updating the firmware, which is a parameter specification for operating the firmware 110. Note that the firmware 110 is copied onto the RAM 107 and executed by the CPU 101.

  The Flash B 112 is a non-volatile memory similar to the Flash A 109, and holds print data, log data, and the like. The Flash B 112 holds a parameter specification 113 before updating the firmware that is used when the setting parameter before updating the firmware is written back to the setting parameter 106 of the EEPROM 105 after the firmware 110 on the Flash A 109 is rewritten. The parameter specification 113 is updated as the parameter specification 111 of the FlashA 109 after the firmware update and the setting parameter before the firmware update is written back to the setting parameter 106 of the EEPROM 105.

  The medium feeding unit 115 is a medium feeding unit that has a cassette in which, for example, A4 size or letter size paper is set, and feeds the paper to the printing unit 104.

  The power supply unit 116 is a power supply unit that supplies predetermined power to the image forming apparatus 100.

  Next, parameter specifications according to the present embodiment will be described. The parameter specification according to the present embodiment represents a parameter specification in which an ID as a parameter identifier for uniquely identifying a parameter and a parameter attribute such as an arrangement described later are associated with each other. FIG. 2 is a schematic diagram illustrating the parameter specification 113 before updating the firmware. The parameter specification 113 according to this embodiment includes a parameter ID 121, a parameter name 122, a parameter attribute type 123, an initial value 124, a size 125, and an arrangement (offset) 126 (hereinafter referred to as an arrangement 126). And have.

  The ID 121 is an ID for uniquely identifying a parameter. The ID 121 is uniquely assigned to the parameter, and is not assigned to another parameter with a different firmware version number. The parameter name 122 is the name of the parameter. The type 123 is one of parameter attributes, and is a parameter type such as a character string type (STRING), a numeric type (INT), or an enumeration type (ENUM). The initial value 124 is an initial value of the parameter. The size 125 is the data length of the parameter. The arrangement 126 is a bit offset from the start address of the setting parameter 106 on the EEPROM 105. Although many parameter attributes exist in addition to those described in this embodiment, only representative attributes are taken up here for ease of explanation.

  More specifically, the parameter name 122 “ModelName” whose ID 121 is “1” represents the model name of the image forming apparatus, and the parameter type 123 is a character string type. The initial value 124 of the parameter is “model”, the data length of the size 125 is “6” bytes, and the parameter is arranged at the head of the setting parameter 106. Next, the parameter name 122 “AdminPassword” whose ID 121 is “2” represents the password of the apparatus administrator, and the parameter type 123 is a character string type. The initial value 124 of the parameter is “12334”, the data length is “4” bytes, and the parameter is arranged at the 100th byte from the top of the setting parameter 106. Here, just because the IDs are continuous does not mean that the IDs are arranged in a continuous region with the setting parameters. The parameter “ModelName” and the parameter “AdminPassword” listed here have consecutive IDs of “1” and “2”, but different IDs may be arranged between the setting parameters. Note that the parameter “AdminPassword” is encrypted and stored in the setting parameter 106, but since a known technique can be used for the encryption method, description thereof is omitted here.

  A parameter name 122 “ModeSize” having an ID 121 of “3” represents the size of paper used for printing such as A4 size and letter size, and the parameter type 123 is an enumerated type. The initial value 124 of the parameter is “12”, the data length is “2” bytes, and the arrangement 126 is “0 × 1FE”. The parameter name 122 “PowerSaveMode” whose ID 121 is “500” represents the time until the power supply unit 116 shifts to the power saving state with low power consumption after a predetermined time has elapsed after the printing is finished. The type 123 is an enumerated type such as 1 minute, 5 minutes, 10 minutes, 30 minutes, 60 minutes, and 120 minutes. The initial value 124 of the parameter is “3”, the data length thereof is “1” bytes, and the parameter is arranged at the end of the setting parameter 106.

  Next, the virtual EEPROM 108 held by the RAM 107 will be described. The virtual EEPROM 108 has different contents held in the RAM 107 before and after the firmware update. FIG. 3 is a schematic diagram of the virtual EEPROM 108A in which the setting parameter 106 on the EEPROM 105 before the firmware update is copied to the RAM 107. FIG. 4 is a schematic diagram of the virtual EEPROM 108B initialized with the parameter specifications after the firmware update. FIG. 5 is a schematic diagram of a virtual EEPROM 108C in which the virtual EEPROM 108B is rewritten with setting parameters before updating the firmware.

  Here, how the virtual EEPROM 108 is created and updated in the RAM 107 will be described with reference to FIG.

  The pre-update parameter definition information 450 is data in which the parameter specification 113 held in the Flash B 112 is expanded in the RAM 106. The pre-update parameter setting value 451 is data obtained by developing the virtual EEPROM 108A on the memory in accordance with the pre-update parameter definition information 450. The updated parameter definition information 452 is data obtained by expanding the parameter specification 111 of the updated firmware 110 on the RAM 107. That is, the state where the EEPROM 105 is copied to the RAM 107 is the virtual EEPROM 108A, the state where the virtual EEPROM 108A is initialized with the parameter definition information 452 of the updated firmware 110 is the virtual EEPROM 108B, and the pre-update parameters are rearranged in the virtual EEPROM 108B Is the virtual EEPROM 108C.

  Then, as shown in FIG. 3, each parameter is arranged in the virtual EEPROM 108A in accordance with the arrangement 126 of the parameter specification 113. More specifically, a parameter name 122 “ModelName” having an ID 121 of “1” is assigned with a data length of “6” bytes at an offset 0 × 0 from the head address holding the setting parameter. Similarly, a parameter name “Adminpassword” with an ID 121 of “2” is assigned to an offset 0 × 100 with a data length of “4” bytes. Parameter name “MediaSize” with ID 121 “3” at offset 0 × 1FE and data length “2”, Parameter name 122 “PowerSaveMode” with ID 121 “500” at offset 0 × 71E and data length “1” bytes It has been.

  FIG. 7 is a diagram for explaining a state in which the virtual EEPROM 108A is temporarily saved in the RAM 107 in order to initialize with the parameter specification 111 after the firmware update.

  The ID-setting parameter relation table shown in FIG. 7A is a fixed length table prepared for each parameter ID 160 before each parameter is saved. The ID-setting parameter relation table is a table for associating the parameter ID 160 with the parameter attribute, but actually associates the parameter ID 160 with the pointer of the address 161 to the memory storing the parameter attribute. This is because the size of the parameter attribute differs for each parameter, and if the parameter ID 160 and the parameter attribute are directly associated, the size of the ID-setting parameter relation table on the RAM 107 becomes very large. As shown in FIG. 7A, if the address 161 of the memory storing the parameter attribute is used instead of the parameter attribute, the data length is fixed to 4 bytes for each parameter. The table size can also be reduced.

  FIG. 7B is a schematic diagram showing a storage memory for each parameter. In saving each parameter, the memory is secured by the size defined by the size 125 of the parameter specification 113 for each parameter, and the data extracted from the virtual EEPROM 108A is stored in the secured memory in the binary format. In the example shown in FIG. 7B, in the parameter name 122 “ModelName” whose ID 121 is “1”, the data length “6” bytes from the address 0 × 500000 is secured in the memory 171 and stored. The situation is shown. Similarly, in the parameter name 122 “AdminPassword” whose ID 121 is “2”, the data length of “4” bytes from the address 0 × 500010 is secured in the memory 171, and the parameter name 122 “MediaSize” whose ID 121 is “3”. In this case, the memory 171 is secured with the data length “2” bytes from the address 0 × 500020, and the parameter name 122 “PowerSaveMode” with the ID 121 “500” has the data length “1” bytes from the address 0 × 501F40. The length is secured in the memory 171 and stored respectively. The parameter name 122 “AdminPassword” whose ID 121 is “2” is formed by a numerical character string having a data length of “4” bytes, but this parameter is stored in an encrypted state. In the parameter specification 113 before the firmware update according to the present embodiment, the number of registered parameters is 500. The parameter name 122 “PowerSaveMode” whose ID 121 is “500” is a parameter registered at the end of the parameter specification 113, and the offset value is the largest value.

  FIG. 8 is a schematic diagram for explaining the parameter specification 111 after firmware update. In the parameter specification 111 after the firmware update illustrated in FIG. 8, the data length of the parameter name 122 “AdminPassword” with the ID 121 of “2” is changed from “4” bytes to “6” bytes. Accordingly, in the virtual EEPROM 108B shown in FIG. 4, the offsets of all parameters arranged behind “AdminPassword” are arranged behind by 2 bytes. Furthermore, the parameter “WirelessLAN” newly added by the firmware update is also added last. All the parameters of the virtual EEPROM 108B shown in FIG. 4 are values of the initial value 124 of the parameter specification 111 after the firmware update. As shown in the EEPROM 108B, the reason for initializing each parameter is that if there is a difference in parameter specifications before and after the firmware update, if the value before the firmware update is written back, the value will be as expected by the user. This is because they do not always behave.

  Once initialized (virtual EEPROM 108B) and then only the parameters whose specifications are not changed are written back to the virtual EEPROM 108 from the temporarily stored setting parameters before the firmware update shown in FIG. Parameters whose specifications have been changed before and after are initialized to the initial values of the updated firmware.

  As shown in the schematic diagram of the EEPROM 108C in FIG. 5, only the parameter name 122 “AdminPassword” whose ID 121 is “2” whose specification has been changed is not written back, and the parameter after firmware update is not written back. The initial value shown in the specification 113 is replaced.

  Next, a process for reflecting the setting parameter before updating the firmware in the setting parameter for operating the updated firmware will be described with reference to the flowchart of FIG.

  The firmware is updated by the CPU 101 executing the firmware developed on the RAM 107. Then, after the image forming apparatus 100 is restarted, the CPU 101 executes the updated firmware developed on the RAM 107 in the same manner, so that the processing from step S400 is performed.

  When the firmware is updated in step S400, the CPU 101 creates a memory image (virtual EEPROM 108A) of the EEPROM 105 on the RAM 107 (step S500). In the subsequent setting parameter processing, the virtual EEPROM 108 is processed until the final setting parameters are written in the EEPROM 105. This is because a general EEPROM has a limit on the number of times of writing, and is a consideration for preventing the life of the EEPROM from being shortened more than necessary by increasing the number of times of writing.

  After creating the virtual EEPROM 108A on the RAM 107, the CPU 101 reads out the setting parameter before the firmware update from the virtual EEPROM 108A based on the parameter specification 113 before the firmware update held by the FlashB 112 (step S502). Then, the CPU 101 stores the read setting parameter in the RAM 107.

  Next, the CPU 101 initializes the virtual EEPROM 108A according to the parameter specification 111 after the firmware update, and creates the virtual EEPROM 108B (step S502). Then, according to the following procedure, the CPU 101 sequentially sets the setting parameters before updating the firmware from the parameter name 122 “ModelName” with ID 121 “1” to the parameter name 122 “PowerSaveMode” with ID 121 “500”. Are rearranged one by one to create a virtual EEPROM 108C.

  In step S503, the CPU 101 confirms whether there is a parameter with the same ID in the parameter specification after the firmware update. If there is a parameter with the same ID (Yes in step S503), the CPU 101 checks the attribute difference before and after the firmware update (step S504).

  That is, the CPU 101 confirms the parameter type (step S505), the initial value (step S506), and the size (step 507). If no difference is found in all the specifications (step S505 none, step S506 none, step S507 none), the CPU 101 writes the value of the virtual EEPROM 108B back to the value before the firmware update (step S508). On the other hand, when there is no parameter with the same ID (no step S503), or when there is a difference in any of the parameter type, initial value, and size (any of step S505, step S506, or step S507) The CPU 101 does not write the value of the EEPROM 108B back to the value before the firmware update.

  When there is a difference in the parameter specifications before and after the firmware update, if the value before the firmware update is written back, the value may not behave as expected by the user, so the specification has changed. The CPU 101 sets a new initial value.

  After the rearrangement of the parameter name 122 “PowerSaveMode” whose ID 121 is “500” is completed, the CPU 101 copies the virtual EEPROM 108C to the EEPROM 105 (step S509).

  Finally, the CPU 101 replaces the parameter specification 113 held in the FlashB 112 with the parameter specification 111 after the firmware update, and ends the process (step S510).

  As described above, according to the first embodiment, it is possible to update the setting parameters before updating the firmware in the binary format based on the parameter specifications, and the encrypted parameters cannot be handled in the text format. Can handle any kind of data.

[Second Embodiment]
FIG. 10 is a diagram for explaining parameter specifications before firmware update according to the present embodiment. The parameter specification 113 ′ according to the present embodiment is a version number 401 newly added to the parameter specification 113 described in the first embodiment. The version number 401 is an attribute attached to each parameter, and when any of the other attributes of the type 123, the initial value 124, and the size 125, excluding the arrangement 126, is changed in the unit of firmware update. The number is incremented by 1 with respect to the version number. The initial version number is “1”, which means that the version number of the newly registered parameter is “1”. As shown in FIG. 10, in the parameter specification 113 ′ before the firmware update according to the present embodiment, the version numbers of the parameters given as examples are all “1”.

  In the first embodiment, it is not possible to confirm whether or not there is a change in the parameter specification without checking each attribute of the parameter specification. It is possible to confirm whether or not there is a change in the parameter specification by only checking whether or not 401 is changed. In the description of the present embodiment, the same portions as those in the configuration and operation described in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 11 is a schematic diagram for explaining the parameter specification 111 ′ after the firmware update according to the present embodiment. In the parameter specification 111 ′ after the firmware update shown in FIG. 11, the specification of the parameter name 122 “AdminPassword” with the ID 121 of “2” is changed before and after the firmware update as in the first embodiment. Therefore, the version number of the parameter name 122 “AdminPassword” whose ID 121 is “2” is “2”.

  Next, a process for reflecting the setting parameter before updating the firmware in the setting parameter for operating the updated firmware will be described with reference to the flowchart of FIG.

  The process shown in the flowchart of FIG. 12 is a series of processes for determining whether or not there is a difference in the parameter specifications related to step S504, step S505, step S506, and step S507 described in the flowchart of FIG. 9 is replaced with a process for determining whether or not there is a difference in the version numbers, and the other processes are the same as those described with reference to FIG. Therefore, only the determination process for determining whether or not there is a difference in the version numbers shown in step S700 will be described here.

  As shown in FIGS. 10 and 11, the version number of the parameter name “AdminPassword” whose ID 121 is “2” is different before and after the firmware update. Therefore, the CPU 101 determines that there is a difference in the version number (Yes in step S700), and does not change the value from the virtual EEPROM 108B. On the other hand, for the parameter name 122 “ModelName” whose ID 121 is “1”, the parameter name “MediaSize” whose ID 121 is “3”, and the parameter name “PowerSaveMode” whose ID 121 is “500”, the version number is the same before and after the firmware update. It remains “1”. Therefore, the CPU 101 determines that there is no difference in the version numbers (step S700: no), and executes an update process for the virtual EEPROM 108B in step S508. Note that the parameter name 122 “WirelessLAN” with the ID 121 of “501” is a parameter that has been newly added after the firmware update, and thus is not updated. The value written in the virtual EEPROM 108B in step S502 remains as it is in step S509. Copied to EERPOM 105.

  As described above, according to the second embodiment, in addition to the effect of the first embodiment, the attribute of the version number indicating the presence or absence of the parameter specification difference is added, so the setting value before updating the firmware for each parameter It is possible to improve the processing speed related to the determination process of whether or not to return to the above. This becomes more effective as the number of parameters and the number of attributes of each parameter increase.

  In the description of the present embodiment, an administrator password (AdminPassword) is given as an example of data that is encrypted and cannot be handled in the text format. However, it is encrypted outside the image forming apparatus and decrypted by the image forming apparatus. It is also effective for data that cannot be converted to

  In the description of the present embodiment, the print function of the image forming apparatus has been described as an example. However, the present invention is not limited to this, and can be applied to all apparatuses having a function of updating firmware.

100 Image forming apparatus 101 CPU
102 receiving unit 103 image processing unit 104 printing unit 105 EEPROM
106 Setting parameter 107 RAM
108 Virtual EEPROM
109 FlashA
110 Firmware 111, 111 'Parameter specification 112 FlashB
113, 113 ′ Parameter specification 114 System bus 115 Medium feeding unit 116 Power supply unit

Claims (8)

A method for updating firmware for operating a device with reference to a parameter setting value stored in a first nonvolatile memory,
A firmware update step for updating the firmware;
A pre-update parameter definition read step for reading parameter definition information including the parameter identifier and arrangement information of the firmware before update from the second nonvolatile memory after the firmware update ;
A pre-update memory image creation step for creating a memory image in the same format as the parameter setting value stored in the first nonvolatile memory before firmware update on the memory;
A pre-update parameter setting value holding step for reading the parameter setting value before firmware update from the memory image and associating it with a parameter identifier and holding it in the memory;
A parameter setting value rearrangement step for rearranging the parameter setting value before firmware update held in the memory according to the parameter arrangement information after firmware update to the memory image;
A first nonvolatile memory writing step of copying the memory image in which parameter setting values are rearranged to the first nonvolatile memory;
A firmware update method comprising: a second nonvolatile memory writing step of writing parameter definition information of the updated firmware on the second nonvolatile memory after the firmware update. The parameter definition information has a version number as an attribute for each parameter, and the parameter setting value rearrangement step includes updating the version number of the parameter definition information before the update of the second nonvolatile memory and the firmware after the update The firmware update method according to claim 1 , wherein the version number of the parameter definition information is compared, and parameters having different parameter version numbers are not rearranged in the memory image before update.   3. The firmware updating method according to claim 1, wherein the parameter setting value held in the pre-update parameter setting value holding step is in a binary format. The parameter definition information has an initial value for each parameter, and the initial value for each parameter is stored in the pre-update memory image according to the parameter definition information after the firmware update before the execution of the parameter setting value rearrangement step. 2. The firmware update method according to claim 1, further comprising a memory image initialization step of writing. A firmware program for updating firmware for operating a device with reference to parameter setting values stored in a first nonvolatile memory,
A firmware update program for updating the firmware;
A pre-update parameter definition read program that reads parameter definition information including the parameter identifier and arrangement information of the firmware before update from the second nonvolatile memory after the firmware update;
A pre-update memory image creation program for creating a memory image in the same format as the parameter setting value stored in the first nonvolatile memory before firmware update on the memory;
A pre-update parameter setting value holding program that reads the parameter setting value before firmware update from the memory image and associates the parameter setting value with a parameter identifier,
A parameter setting value rearrangement program for rearranging the parameter setting values before firmware update held in the memory according to the parameter arrangement information after firmware update in the memory image;
A first nonvolatile memory writing program for copying the memory image in which parameter setting values are rearranged to the first nonvolatile memory;
A firmware program, comprising: a second nonvolatile memory writing program for writing parameter definition information of the updated firmware onto the second nonvolatile memory after the firmware update. The parameter definition information has a version number as an attribute for each parameter, and the parameter setting value rearrangement program updates the version number of the parameter definition information before the update of the second nonvolatile memory and the update of the firmware after the update 6. The firmware program according to claim 5, wherein a version number of the parameter definition information after that is compared, and a parameter having a different version number is not rearranged in the memory image before update . 7. The firmware program according to claim 5, wherein the parameter setting value held by the pre-update parameter setting value holding program is in a binary format. The parameter definition information has an initial value for each parameter, and the initial value for each parameter is stored in the pre-update memory image according to the parameter definition information after the firmware update before the execution of the parameter setting value relocation program. 6. The firmware program according to claim 5, further comprising a memory image initialization program to be written.